Aspects of plant-Insect Pests - Natural Enemies Interactions

Abstract

Some aspects of plant, insect pest and natural enemy interactions were reviewed and coucluded. Plant was the biggest and most important producer in the ecosystem. All energy urilized by organisms was fixed in an utilizable form by plant through photosynthesis. Energy flew in the ecosystem through food chains and food webs in the trophic system. Understanding of food chains and food webs was therefore, foundational to the design and implementation of biological and natural control in pest management. Plant and insect having profound interactions in the ecosystem. Insect species diversity was positively related to plant species diversity and plant structural diversity.
MacArthur and wilson (1967) initiated the idea r-K continuum of that K-strategists were good competitiors and adapted to stable habitats, while r-strategists wee good colonizers and high dispersable. A synoptic model of an insect species was developed by Southwood and Comins (1976.) J-selected species was in stable enironment with density dependent and natural enemies with high natality rate and density independent. Intrinsic and extrinsic defenses of plant were shown by Van Emden and Way (1972.) Intrinsic defense included physical morphors of plant, toxins and phytochemicals. Extrinsic defense was plant benefitial from natural enemies in term of natural enemies reducing numbers of abundance of herbivors, therefore plant gained more chance to survive. Integration of plant resistance and biological control among trophic levels in pest mangement, was one of methods that sustained natural resources in the agricultural ecosystem.